The present invention relates to a chain and flight conveyor for use in conveying materials in the mining industry, and, in particular, to an improved design of a chain and flight conveyor having an improved drive sprocket assembly. Still more particularly, this invention relates to conveyor chains for continuous miners and chain haulage units.
Conveyor chains for use on continuous miners and chain haulage units must have the ability to flex sideways to allow them to make turns. For this purpose, they include swivel links. Unlike a link from a standard roller or stud-brushed chain, a swivel link cannot be sprocket-driven on its interior, because the space within it is mostly filled with the swivel pin and the lugs that surround the swivel pin. A swivel link can only be sprocket driven on its outer ends.
The chains are driven by a single sprocket aligned with the center of the chain as viewed from above. As the swivel link can only be driven on its ends, not its interior, this means that the sprocket can only drive every other pitch, reducing the number of teeth on the sprocket by half. The result is faster sprocket wear, and rougher and noisier chain/sprocket interaction. It is also more likely that the chain will come off of the sprocket in certain conditions.
One of the principal objects of this invention is provide an improved conveyor chain and flight assembly that permits driving of every link in a swivel chain.
This invention provides a conveyor including a pan, and a conveyor chain and flight assembly that travels over the pan. The conveyor chain and flight assembly includes a first link assembly and a second link assembly, each of which includes two spaced apart drive pins, each of which has a first end and a second end, and two spaced apart side plates, each of which has two spaced apart openings, each opening receiving a different one of the drive pins. The conveyor chain and flight assembly further includes drive pin retaining means for retaining the drive pins in the side plates, and a swivel assembly connecting the two link assemblies, the swivel assembly including a swivel pin, a male connecting lug, and a female connecting lug. The male connecting lug has a base having a horizontal bore that receives one of the drive pins of the first link assembly, and a tongue connected to the base, and the female connecting lug has a base having a horizontal bore that receives one of the drive pins of the second link assembly, and a spaced apart upper lip and lower lip connected to the base. The male connecting lug tongue extends between the spaced apart lips, and each of the lips and the tongue have openings therein that form a bore through the male and female lugs that receives the swivel pin. The swivel link further includes swivel pin retaining means for retaining the swivel pin in the lugs. The conveyor chain and flight assembly further includes a first flight connected to one of the first and the second link assemblies, the flight having a flight head having two spaced apart indentations, each of which receives a different one of the first ends of the drive pins, and first flight securing means retaining the drive pin first ends in the first flight head so that the first flight head is spaced from its respective side plate. The conveyor chain and flight assembly further includes a second flight connected to the one of the first and the second link assemblies, the flight having a flight head having two spaced apart indentations, each of which receives a different one of the second ends of the drive pins, and second flight securing means retaining the drive pin second ends in the second flight head so that the second flight head is spaced from its respective side plate. The conveyor chain and flight assembly further includes a sprocket drive including two spaced apart drive sprockets, with each drive sprocket engaging the drive pins between the side plates and the side plate""s respective flight.